Shuttering plywood is a kind of building plank widely used in building concrete pouring. Shuttering plywood generally refers to film faced plywood It is made of waterproof surface film and birch core board by hot pressing at high temperature.

As a kind of building material, shuttering plywood is mainly used in various high-rise buildings, dams, tunnels and other construction buildings. This kind phenolic plywood is made of new waterproof materials by pressing at high temperature, and has very strong compression resistance and corrosion resistance, so it is widely used.

Shuttering plywood is a temporary support structure, which is made according to the design requirements. The concrete structure and members can be formed according to the specified position and geometric size, maintain their correct position. And bear the self weight of the building formwork plywood and the external load acting on them. The purpose of shuttering plywood engineering is to ensure the quality and construction safety of concrete engineering, accelerate the construction progress and reduce the project cost.

The shuttering plywood structure used for the construction of cast-in-situ concrete structure engineering is mainly composed of three parts: panel, support structure and connector. The face plate is a bearing plate that directly contacts the fresh concrete.

The supporting structure is a temporary structure that supports the panel, concrete and construction load to ensure that the building formwork structure is firmly combined without deformation and damage.

The connector is a fitting that connects the panel and the supporting structure as a whole.

Advantages of Shuttering plywood

1. The surface of shuttering plywood is relatively flat and smooth, and the surface is made of phenolic resin and other materials, so its water resistance is good. The surface of shuttering plywood is suitable for concrete compaction. The process is complex and the surface is rough.

2. As the surface of the fair faced formwork is relatively flat, the decoration effect is good, and there is generally no trace left after the remova. The decorative property of the mixed formwork is poor because of its rough surface.

3. Shuttering plywood can be used repeatedly, so the overall cost is relatively low.

4. The film faced shuttering plywood needs to be poured with concrete. And the surface of the shuttering plywood needs to be plastered, while use the formwork plywood process is relatively simple. because film shuttering plywood with flat and smoonth surface.

4. The sanded panels surface can do anti slip. It is applicable to plant or trailer flooring.

Bonding properties of shuttering plywood

Difference of commercial plywood, shuttering plywood used for concrete formwork is a type I plywood with high weather resistance and water resistance, and the adhesive is phenolic resin glue.

This type adhesive of shuttering plywood has high bonding strength, good water resistance, heat resistance, corrosion resistance and other properties. And its outstanding performance is excellent in boiling water resistance and durability. There are also chemically modified phenolic resin adhesives.

The main indicators of bonding performance are bonding strength and durability.

The bonding strength is the initial bonding performance, which means that the veneer is completely glued and has sufficient strength after bonding;

Glue durability is the long-term glue performance, which means that the glue remains good after a certain period of time.

The above two indicators can be judged by glue bonded strength test and boiling water immersion test. The shttering plywood test provide by shuttering plywood manufacturer or shuttering plywood supplier.

When purchasing plywood panels for concrete formwork, it is necessary to determine whether it belongs to Class I plywood. To determine whether the batch of plywood is made of phenolic resin glue or other adhesives with equivalent properties. If limited by the test conditions, when the bonding strength test cannot be done, it can be quickly judged by boiling small pieces of test pieces.

Shuttering plywood with phenolic resin as an adhesive will not open after being boiled.

Carrying Capacity of shuttering plywood

The load-bearing capacity of shuttering plywood is related to the thickness, static bending strength and elastic modulus of the plywood. Due to the different tree species and production areas of the plywood, the mechanical properties of the plywood are also different.

If you need to test the bearing capacity of plywood, you can entrust a professional organization to test the static bending strength and elastic modulus for confirmation.

These tests are also generally available from shuttering plywood manufacturers.

The standards required by each country and region are different. Therefore, special standard equipment shall be selected when testing the mechanical properties of shuttering plywood. The test shall be conducted according to relevant test standards. In this way, the correct mechanical properties of the film faced plywood can be obtained.

Generally speaking, the timber sheet material mechanical properties of birch plywood used as phenolic film faced plywood are excellent.

Because birch ply has high hardness and density.

Construction Configuration of Shuttering Plywood

Simple structural components can be prepared by directly listing template specifications and quantities according to structural construction drawings. The thickness and spacing of shuttering plywood can be calculated according to the configuration of the support system.

The entire sheet is used directly, and random sawing is minimized, resulting in waste of plywood.

(1) The common thickness of shuttering plywood is generally 12 or 18mm, which can be adjusted according to the thickness of the plywood through design calculations.

(2) The support system can use steel pipe scaffolding, or wood or H20 beams. When using solid wood as support, pay attention to the deformation factors of solid wood support.

(3) The length of the nails should be 1.5 to 2.5 times the thickness of the formwork plywood. And at least 2 nails should be nailed at the overlap of each formwork plywood and the corrugated wood.

 

Shuttering plywood as wall and floor formwork construction process

film faced shuttering plywood, as a formwork for cast-in-place concrete walls and floors, is a commonly used formwork technology. Compared with the use of combined formwork, it can reduce the joints on the exposed surface of concrete and meet the requirements of fair-faced concrete.

When installing the wall formwork, first make one side formwork according to the side line, temporarily support it with supports. Fix the traction bar after correction, and then fix it with diagonal braces.

When large-area side templates are assembled, the upper and lower vertical seams should be staggered from each other.

In order to ensure the correct thickness of the wall, small square wood can be used between the concrete form boards on both sides. And the waterproof concrete wall should be supported by a water stop plate. The small square wood should be taken out one by one along with the pouring concrete.

When installing the floor formwork concrete form shuttering plywood, nail the support according to the horizontal line. And the upper end of the support is aligned with the horizontal line. Then place the supports in the middle part, and finally lay the floor concrete form phenolic ply on the supports in the middle part.

Precautions for the use of shuttering plywood

(1) shuttering plywood increases the durability of the board surface, has good demoulding performance, and has a smooth and smooth appearance. It is most suitable for fair-faced concrete projects with special requirements. And no finishing treatment on the outer surface of the concrete, such asBuildings, dams, power stations, bridges, etc.

(2) Clean the shuttering plywood surface as much as possible after demoulding, and stack it neatly;

(3) When the formwork plywood is removed, it is strictly forbidden to throw it, so as not to damage the surface treatment layer;

(4) The corners of shuttering plywood are generally waterproofed, so when cutting into small pieces, it is necessary to waterproof the cutting parts;

(5) Try not to drill holes on the board surface. In case of reserved holes, they can be filled with ordinary wooden boards.

(6) Repair materials should be available on site so that the damaged panels can be repaired in time.

(7) Brushing the release agent before use can increase the service life.

When designing large-area side templates, one side formwork should be staggered. Temporarily provide it with assistance, fix the traction bar after correction, and then fix it with diagonal braces.

According to the support requirements, the thickness of the formwork, the section and spacing of the rungs, and the corrugated wood can be determined and selected.

Storage of shutting plywood

During transportation and storage, severe deformation of shuttering plywood and aging of surface coating caused by sunshine and rain shall be avoided.

At the construction site, the formwork shall be stored on a flat, level and dry site, with at least three 10 * 10cm wooden beams horizontally supported at the bottom.

When designing large-area side templates, one side formwork should be staggered, temporarily provide it with assistance, fix the traction bar after correction, and then fix it with diagonal braces.